The present invention relates generally to the field of rechargeable batteries. More particularly, the present invention relates to a method and apparatus for the detection of the end-of-life for a rechargeable battery.
Computer systems have become increasingly pervasive in our society. The processing capabilities of computers have increased the efficiency and productivity of workers in a wide spectrum of professions. As the costs of purchasing and owning a computer continues to drop, more and more consumers have been able to take advantage of newer and faster machines. Furthermore, many people enjoy the use of notebook computers because of the freedom. Mobile computers allow users to easily transport their data and work with them as they leave the office or travel. This scenario is quite familiar with marketing staff, corporate executives, and even students.
A similar phenomenon has occurred with other types of electronic devices. A recent plethora of portable devices allow users to work and play free restrictive power cords and adapters. As people work outside of their traditional office, they often find themselves using their notebook computers, cellular phones, digital assistants, etc. as if in a portable office. Similarly, people enjoying themselves away from the home have taken advantage of music players, digital cameras, electronic games, etc. while on the road or outdoors. All of these electronic devices operate on battery power. More particularly, a significant number of the devices use some type of rechargeable battery source.
But over time, even a rechargeable battery will become useless. The ability of a rechargeable battery, to recharge, diminishes over time with its use. Furthermore, certain types of battery technologies do not hold a charge over the entire life of the battery. As a battery is charged, its ability to hold the maximum designed capacity charge reduces with each charging cycle. Unfortunately, users are seldom aware of such a condition and are caught flatfooted when a rechargeable battery does fail.
Some electronic devices such as a notebook computer may include a operating system power management (OPSM) mechanism to track the system power. One existing OSPM utility provides a type gas gauge information in regards to a battery. For example, this utility calculates the remaining battery life as:                               Remaining          ⁢                      xe2x80x83                    ⁢          Battery          ⁢                      xe2x80x83                    ⁢          Life                                              (                      in            ⁢                          xe2x80x83                        ⁢            hours                    )                      =            Remaining      ⁢              xe2x80x83            ⁢      Battery      ⁢              xe2x80x83            ⁢      Charge              Battery      ⁢              xe2x80x83            ⁢      Present      ⁢              xe2x80x83            ⁢      Discharge      ⁢              xe2x80x83            ⁢      Rate      
Only the remaining battery life are watched by the utility. However, the capabilities or physical condition of the battery itself are not evaluated.